Privacy glass, defined as glass which has a low visible transmittance (i.e., less than or equal to 50%), can be used in a variety of applications such as automotive applications and architectural applications. There are generally no limitations regarding where privacy glass can be incorporated in a building. In some automotive applications, privacy glass can only be incorporated in the rear window and rear sidelights due to the regulations imposed in the United States and some other countries.
Typically, a substrate, either coated or uncoated, that will be used as privacy glass is highly absorbtive or is highly reflective in the visible region of the electromagnetic spectrum. For example, the privacy glass can comprise an uncoated, tinted glass substrate with good absorptive properties in the visible region. In the alternative, the privacy glass can comprise a coated, clear glass substrate with high reflectivity in the visible region. In another alternative embodiment, the privacy glass can comprise a laminated product formed, for example, with a tinted substrate and a clear, coated substrate.
The present invention provides a novel coating that can be used to transform a glass substrate into privacy glass. The coated substrate of the present invention exhibits reduced visible reflectance, which is aesthetically desirable, while providing solar reflection in the infrared region on at least one side of the substrate which reduces the heat load.